(1) Field of the Invention
The present invention relates to a liquid crystal display device with an input function, and in particular to a liquid crystal display device having a built-in capacitive coupling touch sensor function.
(2) Description of the Related Art
Capacitive coupling touch sensors are devices that are combined with display devices and have such a function as to detect the point where a touch sensor screen corresponding to the display region of the display device is touched with the finger by detecting the change in capacitance between the tip of the finger and a location detecting electrode, so that the coordinates of the point can be inputted into the display device.
In recent years touch sensors have been used in mobile apparatuses, such as cellular phones and microminiature personal computers, as input devices to be combined with the display device.
Capacitive coupling touch sensors are provided with a transparent electrode that is formed on the touch sensor screen on top of the touch sensor substrate corresponding to the display region of the display device and patterned so as to be able to detect the touched point, wires for taking out a location detecting signal from a transparent electrode formed around the periphery of the touch sensor screen, and a wire circuit for outputting a location detecting signal to an external detection circuit.
An example of a liquid crystal display device with a touch sensor made of a capacitive coupling touch sensor device and a liquid crystal display devices that are pasted together is given in JP2006-023904A.
Examples of capacitive coupling touch sensor functions that are built-in in liquid crystal display devices are given in JP2008-185785A, which relates to an in-plane switching driving mode liquid crystal display device, and JP2008-32756A, which relates to twisted nematic (TN) mode and vertical alignment liquid crystal display devices.